FlightRecord

Islip (ISP) to Baltimore (BWI): On-Time Performance

Data through May 2026

When you fly ISP to BWI matters as much as anything else about the booking: the route swung from 96% on-time in September 2025 to just 73% in July 2025. Across the full period the route averages 85% on-time against a national 78%. Morning departures also hold up better than evening ones (93% vs 72%), which matters most in the rough months.

On-time
85%
arrived <15 min late
Avg delay
11 min
completed flights
Cancelled
1.0%
Flights/day
3.3
last 12 months
Duration
1h 18m
scheduled
Distance
220 mi

Monthly on-time trend

Monthly on-time percentage for ISP to BWI flights50%75%100%June 2024: 86% on-time (121 flights)86Jun 2024July 2024: 75% on-time (127 flights)75August 2024: 75% on-time (100 flights)75September 2024: 94% on-time (94 flights)94Sep 2024October 2024: 94% on-time (93 flights)94November 2024: 93% on-time (89 flights)93December 2024: 91% on-time (94 flights)91Dec 2024January 2025: 90% on-time (89 flights)90February 2025: 95% on-time (82 flights)95March 2025: 87% on-time (89 flights)87Mar 2025April 2025: 91% on-time (106 flights)91May 2025: 76% on-time (114 flights)76June 2025: 79% on-time (123 flights)79Jun 2025July 2025: 73% on-time (128 flights)73August 2025: 80% on-time (97 flights)80September 2025: 96% on-time (90 flights)96Sep 2025October 2025: 89% on-time (93 flights)89November 2025: 88% on-time (90 flights)88December 2025: 77% on-time (93 flights)77Dec 2025January 2026: 88% on-time (93 flights)88February 2026: 85% on-time (84 flights)85March 2026: 76% on-time (90 flights)76Mar 2026April 2026: 90% on-time (106 flights)90May 2026: 94% on-time (114 flights)94

Best time to fly from ISP to BWI

Aim for departures around 8 a.m. (98% on-time); avoid 6 p.m. departures (65%).

On-time percentage by scheduled departure hour, ISP to BWI5 a.m.: 95% on-time (316 flights)56 a.m.: 96% on-time (414 flights)68 a.m.: 98% on-time (44 flights)89 a.m.: 96% on-time (68 flights)910 a.m.: 87% on-time (158 flights)1011 a.m.: 85% on-time (163 flights)1112 p.m.: 84% on-time (310 flights)121 p.m.: 84% on-time (121 flights)132 p.m.: 65% on-time (105 flights)143 p.m.: 80% on-time (140 flights)154 p.m.: 84% on-time (213 flights)165 p.m.: 73% on-time (255 flights)176 p.m.: 65% on-time (73 flights)18scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday83%17 min
Tuesday86%9 min
Wednesdaybest88%8 min
Thursday85%11 min
Friday85%10 min
Saturday87%9 min
Sunday84%12 min

What causes delays on this route

Share of total delay minutes by cause, as reported by carriers to the US DOT.

  • Late-arriving aircraft45%
  • Airline operations29%
  • National airspace system24%
  • Weather2%

Frequently asked questions

How often are flights from ISP to BWI delayed?
15% of ISP–BWI flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 11 minutes.
What is the best time of day to fly from ISP to BWI?
Departures around 8 a.m. have the best record (98% on-time), while departures around 6 p.m. have the worst (65%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from ISP to BWI?
The scheduled ISP–BWI flight time averages 1h 18m over 220 miles. Actual arrival times vary — flights on this route land 15+ minutes late 15% of the time.
How often are ISP to BWI flights cancelled?
1% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
What is the worst month to fly from ISP to BWI?
July 2025 was the roughest month in this dataset, with only 73% of arrivals on time. The best was September 2025 at 96%. If your dates are flexible, that 23-point gap is worth planning around.

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Based on 2,399 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.